Abstracts

Rationale: Antiepileptic drugs (AEDs) are the mainstay of treatment for patients with epilepsy. Adherence to the prescribed drug regimen is a major step in achieving the goal of reduced seizure burden in patients with epilepsy. Decreased AED adherence is associated with more than a 3-fold increase in mortality. Periods of nonadherence in patients with epilepsy were also associated with significantly more emergency department visits, hospital admissions, injuries and fractures. Adherence can be measured using the Medication Possession Ratio (MPR). This is a numerical value calculated from refill records. Many patients with epilepsy also have obstructive sleep apnea (OSA). One treatment option for patients with OSA is continuous positive airway pressure (C-PAP). Adherence to this non-pharmacologic device is a key factor in treatment success; especially for patients with epilepsy. For patients who are prescribed C-PAP, they bring in a piece of their C-PAP machine with them to their clinic visits that allows the practitioner to download a number of clinical parameters. The parameters include an indicator of how often the patients use their device. Our purpose is to compare two measures of adherence in patients with epilepsy and concomitant OSA. Our hypothesis is that patients with epilepsy and OSA will have similar measures of adherence to their AEDs (as measured by MPR) and usage of their C-PAP machines.Methods: Adult patients seen in the outpatient clinic with a dual diagnosis of epilepsy and OSA are approached about study interest. They must be able to provide consent and complete the study surveys on their own. Eligible patients must be taking an AED and using C-PAP for at least the past 3 months. Twenty patients will be recruited for this pilot cross-sectional study. Patients complete a two-page survey asking questions about adherence to their AED regimen and their C-PAP usage. Additionally, demographic information is collected. Beyond the subjective data on adherence, each patient's community pharmacy provider is contacted to obtain their AED refill history records over the last 3 months. An MPR greater than 0.8 is considered ""adherent"". C-PAP adherence is assessed from their device and the same cut-off is used to categorize ""adherent"" to their C-PAP (greater than 80% usage).Results: Five patients (3 male, 2 female) have been recruited. Their average age is 52.2 years. Three of the 5 patients had AED MPRs greater than 0.8; consistent with being AED adherent. Interestingly, only one of the 5 patients were ""adherent"" with C-PAP (greater than 80% usage for at least 4 hours). Data from all 20 patients will be presented at the meeting.Conclusions: At the time of this writing, patient recruitment is not complete. For the five patients we have recruited, it is surprising that the C-PAP adherence data is so poor. We anticipate that the full dataset generated from this pilot project will help define the scope of adherence in patients with epilepsy and OSA. Knowing this will aid in our clinical and educational approach to these patients and will guide future adherence intervention projects.